The hourglass mark on its dorsum is attractive, and that is why I call it the time keeper. We found this frog while we were cleaning and pruning the area around our fish pond. Sarah was throwing away some rotten twigs and leaves when she felt something cold and creepy leap on to her

The photos above and below are of the same frog, taken a few minutes apart. It changed its color from an off-white to a brownish tone! This happened when the frog had moved from its previous location into a bunch of dried leaves and twigs. Such an ability of animals to change its color is called metachrosis.

Metachrosis could be due to several reasons: like the light/temperature/moisture play a vital role in changing the colour. Some amphibians exposed to cold temperature and darkness often exhibit a darkening of their skin due to a melanophorotropic hormone (dark brown – black pigments) release. At higher temperature and light their color tend to get pale due to melanophore contraction. This color change is probably done as part of a hydro-thermal regulation (for regulating its moisture and temperature).

We are not sure if this frog exhibited metchrosis for such a regulation. At first sight we felt it was an instance of “crypsis“, where the animal has the ability to avoid getting noticed, through camouflage, mimicry, etc. However, studies shows that crypsis alone may not be the case of frogs like this one, and hydro-thermal regulations also play a major role. So probably a short time between the dried leaves with less light and colder environment let it change the shade from pale to dark.

The frog in the picture is polypedates occidentalis. To my amazement, the species was identified and named only recently, in 2006 (link provided below). Hence data is deficient to tell if p.occidentalis is a rare species or not. Probably it is a common species for the western ghats region.

A similar frog is the Common Indian Tree Frog, polypedates maculatus, which also has an hourglass like mark on its dorsum. This one is present in central India and neighboring countries.

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Date: 26 Oct 2008
Location: @ home, Kottayam, Kerala, India
Camera: Nikon D80 + Tamron SP AF90mm f/2.8 Di Macro Lens

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References:
1. Feder M. E., Burggren W. W., 1992: Environmental physiology of the amphibians, University of Chicago Press.
2. Das I., and Dutta S. K., 2006: New Species of Polypedates (Anura: Rhacophoridae) from the Western Ghats, Southwest India, Journal of Herpetology, 40, 2, 214-220 [link].
3. Dr. K. V. Gururaja, Indian Institute of Science, Bangalore.

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P.S. It has been a while since I posted the last article. Time has been flying since pratyahara, and work also is getting tight these days. Anyways timekeeper is here to save me for a while Buon Anno!

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The two tailed spiders are called so because their rear spinnerets are longer than usual, and appear like tails. Spinnerets are the organs with which the spiders spin their silk. In the picture below, you can see the tail pair of spinnerets kept together in its rear. Legs, except the third pair, are very long and slender and have banded colors.

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Its unique habit of skittering on the water surface was first recorded by the Mughal Emperor Babur (1483-1530) in his autobiography. This is the skittering frog, also known as the Indian skipper frog, a common frog widely distributed throughout South Asia.

I was surprised and happy to find that such details were recorded by the first Mughal Emperor of India. I was more surprised to know that Babur had indeed written an autobiography! Babur came from Persia, and his views on the newly conquered Hindustan are written in his biography. Links to the translated pdf version is given below with the references.

Babur writes, along with the events of the year 932: “The frogs of Hindustān are worthy of notice. Though of the same species as our own, yet they will run twelve or fourteen feet on the face of the water”.
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You all liked the winter-snow photographs which I had posted in the previous article - but if they seem dull, grim and harsh, here are some to smile on!! From 2006 Winter.

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There was a time when I used to walk these snow laden roads every day, for more than 3 years. Now when I come to think of it, or see these photographs, I shudder, and wonder how I survived those days  These photographs are from the small street just out of the apartment where I lived during my PhD days at Sapporo in Hokkaido, Japan.

These selected photographs are simple, but I feel there is something strong about it. The elements in it, a man, a dog, and a crow says so.

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